It was the day the soldier accused of the biggest intelligence leak in US history came face-to-face with the computer hacker who first turned him in. Bradley Manning's defence team sought to score early points at his trial by pressuring Adrian Lamo to concede he never got the impression Pte Manning was motivated by hatred for America.

The exchange marked a moment of unexpected drama on just the second day of the court martial under way behind the gates of the Fort Meade Army base. “At any time, did Pfc. Manning ever say he wanted to help the enemy?” David Coombs, a lawyer for the defence, asked. “Not in those words, no,” Mr Lamo said.

Coombs later asked: “At anytime did he say the American flag didn't mean anything to him?”. Mr Lamo replied: “No”.

Demonstrating that Pte Manning acted maliciously when he sent his trove of classified material to the anti-secrecy website founded by Julian Assange will be key to the prosecution case. By contrast, the defence has signalled its intention to show that their client was acting out of a benign, if naïve, sense of duty in the hope of alerting Americans to what was being done in their names in the Iraq and Afghanistan wars.

Another prosecution witness, Mark Johnson, a civilian digital forensic examiner with the US Army's Computer Crimes Investigation Unit, told the court he had found three items of interest on the defendant's laptop, which was seized after his arrest from his base close to Baghdad in May 2010, including a video and contact information for WikiLeaks.

But when another of Pte Manning's lawyers, Major Thomas Hurley, asked the witness under cross-examination if he had found “anything indicating hatred of America” he replied: “No, but we would have noted it. We didn't find it.”

It was said that Lamo compiled his chats with Pte Manning into a file, saved on his computer as “Brad_confession.”

The trial later heard from intelligence trainers who allege they taught Pte Manning in 2008 about the significance and methods of handling sensitive information. It was alleged that the soldier was given “corrective training” - a military training technique used to hone in on particular deficiencies - that same year he posted a video on YouTube that was thought to be classified.

Pte Manning, who is a dual American-British national because his mother is Welsh, has attracted supporters around the globe who laud him as a whistle-blowing hero for peeling some of the shroud from what they see as America's arrogant exercise of foreign policy. Mr Assange, who has been holed up for months in the Ecuadorian Embassy in London, condemned the court martial as a 'show trial'.

“This is not justice; never could this be justice,” he said in a statement. “The verdict was ordained long ago. Its function is not to determine questions such as guilt or innocence, or truth or falsehood. It is a public relations exercise, designed to provide the government with an alibi for posterity.”

Pte Manning has agreed that the trial be heard by the presiding judge, Colonel Denise Lind, instead of by a jury of his peers. With more than 100 witnesses expected for the prosecution, possibly including a member of the Navy Seal team that assassinated Osama bin Laden, it is expected to last until the end of August.

Also speaking out for him in London was gay rights organiser Peter Tatchell. “Every solder in every nation has a duty to expose war crimes. That's what Bradley Manning did,” he offered. “In many ways, Manning is a true patriot because he's sought to uphold the US constitution. Thanks to Bradley, the American people now know the truth.”

Meanwhile a raft of Hollywood celebrities including Russell Brand, Maggie Gyllenhaal, and Wallace Shawn joined Oliver Stone, Rage Against the Machine Guitarist Tom Morello in a short trailer designed to raise awareness of the Bradley Manning trial that was released online.

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